Vulnerability-Lookup

GHSA-2M9Q-5W5G-JWFP

Vulnerability from github – Published: 2025-10-15 09:30 – Updated: 2026-10-21 15:40

Details

In the Linux kernel, the following vulnerability has been resolved:

bpf: Check the helper function is valid in get_helper_proto

kernel test robot reported verifier bug [1] where the helper func pointer could be NULL due to disabled config option.

As Alexei suggested we could check on that in get_helper_proto directly. Marking tail_call helper func with BPF_PTR_POISON, because it is unused by design.

[1] https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2025-39990"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-10-15T08:15:37Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Check the helper function is valid in get_helper_proto\n\nkernel test robot reported verifier bug [1] where the helper func\npointer could be NULL due to disabled config option.\n\nAs Alexei suggested we could check on that in get_helper_proto\ndirectly. Marking tail_call helper func with BPF_PTR_POISON,\nbecause it is unused by design.\n\n  [1] https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com",
  "id": "GHSA-2m9q-5w5g-jwfp",
  "modified": "2026-10-21T15:40:11Z",
  "published": "2025-10-15T09:30:17Z",
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39990"
    },
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    },
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      "type": "WEB",
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CVE-2025-39990 (GCVE-0-2025-39990)

Vulnerability from cvelistv5 – Published: 2025-10-15 07:56 – Updated: 2026-10-21 12:37

Title

bpf: Check the helper function is valid in get_helper_proto

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Check the helper function is valid in get_helper_proto kernel test robot reported verifier bug [1] where the helper func pointer could be NULL due to disabled config option. As Alexei suggested we could check on that in get_helper_proto directly. Marking tail_call helper func with BPF_PTR_POISON, because it is unused by design. [1] https://lore.kernel.org/oe-lkp/202507160818.68358831-lkp@intel.com

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-15 21:55 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6856 records in the last 180 days details

References

4 references

URL	Tags
https://git.kernel.org/stable/c/dfbff47f120e4b079…
https://git.kernel.org/stable/c/3d429cb1278e995e2…
https://git.kernel.org/stable/c/6233715b4b714068d…
https://git.kernel.org/stable/c/e4414b01c1cd9887b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f470378c7562a2818b45ed11c98973f2b89eedd3 , < dfbff47f120e4b0793ca0e0b8660361ccac25a74 (git) Affected: f470378c7562a2818b45ed11c98973f2b89eedd3 , < 3d429cb1278e995e22995ef117fa96d223a67e93 (git) Affected: f470378c7562a2818b45ed11c98973f2b89eedd3 , < 6233715b4b714068d6c831d214a4e8792109875a (git) Affected: f470378c7562a2818b45ed11c98973f2b89eedd3 , < e4414b01c1cd9887bbde92f946c1ba94e40d6d64 (git)
Linux	Linux	Affected: 5.8 Unaffected: 0 , < 5.8 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.50 , ≤ 6.12.* (semver) Unaffected: 6.16.10 , ≤ 6.16.* (semver) Unaffected: 6.17 , ≤ * (original_commit_for_fix)

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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